I posted to TWV2, saying that my improvement came from a combination of reading books on the art and craft of writing, and from reading the works of other writers and picking them apart. That aspect of being a writer has actually made reading a little less enjoyable. Another item I mentioned was simply the practice of writing led to growth.
But really I can think of other ways I improve as a writer.
- Critique groups. I've been a member of four different real life critique groups, and five (I think) on-line critique groups. Most of the on-line ones were for poetry. I estimate that I've critiqued at least a thousand poems. I printed many of those critiques and have them in notebooks, waiting to be gone through and perhaps culled and consolidated. I learned so much from critiquing poetry. When I started that, I knew little about poetry, but knew I had to learn and learn fast. So I studied up, was a fast learner, and feel much more confident in my poetic knowledge and abilities.
- Classes. Most of the ones I've taken have been during writers conferences. I went to one locally that turned out to be something I wasn't expecting. I still have many more to take.
- Old textbooks. I pick these up at thrift stores for 50 cents or a dollar. I'm slowly working through them as reading time allows (which it hasn't for over a year now). I have gleaned much from these, even the older ones.
- Writer Networking. This is both on-line in various discussion forums, as well as the few real life writer contacts I maintain. Those contacts include editors and agents as well.
Certainly improvement in the writing arts, which involve the mind only, will be beyond the reach of some, who were not given complete mental faculties. But for the large majority of people, significant improvement is possible. Whether a large number of people can improve enough to result in becoming published I don't know. Most people won't go to the trouble to try to improve enough for that.